The E-11 was the Standard issue stormtrooper weapon. It could be used for medium to short ranges.
The DLT-19 was used by Imperial shock troopers. This weapon is a rapid fire and had a high fire rate. Could deal high amounts of damage at long ranges.
The DLT-20a was a sniper rifle that most scout troopers used.
The E-11d was a simmilar variant to the E-11 but with modifications that enhances its performace in the battlefield. This gun was usually used by the Death troopers.